When Tamara Ouspenskaia joined Rockefeller’s graduate program in 2010, she arrived intending to study the growth and progression of cancer. But in the course of her studies, she discovered stem cells. She never looked back.
Much cancer research is done in mice, and manipulating mouse genes can be tedious—it often takes a year or more to get results. In the lab of Elaine Fuchs, Tamara was paired with a postdoctoral fellow who had recently developed a new and faster technique to add or remove genes in mice. As a master’s student at McGill University, Tamara had focused on cellular processes that lead to the development of cancer. But after learning her colleague’s technique she was inspired to apply it to new challenges.
Tamara decided to investigate how hair follicles develop from stem cells in the skin. “I thought maybe we could find out something interesting about the molecular signals that occur inside cells as they divide and specialize,” Tamara says. The project didn’t directly relate to cancer, but her mentor agreed it was worthwhile.
Tamara’s change of research focus tells an important story about how Rockefeller scientists are given the support to follow their instincts and blaze their own scientific paths.
“At Rockefeller you find tremendous support, a truly collaborative environment, a brilliant and engaged faculty, and a marvelous freedom to follow your scientific heart.”
The elusive origin of stem cells
It turns out that hair follicles provide an excellent way to study stem cells. These tiny organs in our skin are an abundant and accessible source of stem cells that frequently regenerate to produce hair, cycling through states of quiescence and activation. Like many other stem cells present in adult tissues, hair follicle stem cells reside in specialized microenvironments known as niches.
What sparked Tamara’s curiosity was what happens in the follicle before adulthood, during development. “Does the niche or the stem cell come first?” she asks. “Do the stem cells already reside in a developing hair follicle, or do they appear later?”
It’s a chicken-and-egg sort of question, and what Tamara discovered is that it takes both the chicken and the egg. Her results, which she published in Cell, show that when a stem cell divides to produce two daughter cells, one daughter becomes the stem cell and the other daughter acts as a sort of temporary niche, supporting the first daughter. This second cell sends signals to its sister telling it to maintain its “stemness”—to divide and produce more stem cells rather than specializing.
Later, when this sister is no longer needed, it degrades and disappears altogether. But the stem cell remains for the rest of the organism’s life. It’s an important finding, Tamara says, that might have implications for how stem cells can be used in regenerative medicine.
An inspiring, family-friendly environment
“Science is hard work; it takes a lot of hours,” Tamara says. Both she and her husband are scientists, with a two-and-a-half-year-old daughter and a second child coming. They live in on-campus housing, and their daughter is enrolled in Rockefeller’s Child and Family Center, which provides care for infants, toddlers, and preschoolers within the Rockefeller community. “I asked my husband the other day if he thought our choices would have been different if I’d ended up in another place. Would I still have a paper in a top-tier journal—and a toddler?” she laughs. “Probably not.”
“The fact that my child can be here close to me is amazing,” Tamara says. “It allows for so much flexibility.” Because Rockefeller students pay no tuition, and daycare and housing are subsidized, families like Tamara’s do not end up saddled with debt.
“Rockefeller is a hub for scientists and they come here from all over the world,” Tamara says. “It’s important to be inspired. It’s important to hear other scientists discuss what they’re doing. Rockefeller has exposed me to all kinds of research and so many different scientists, giving me a never-ending source of ideas about what I can do in the coming years.”